tabaghak/dlh-snowflake-mcp-server

DLH Snowflake MCP Server

A Model Context Protocol (MCP) server that provides tools for interacting with Snowflake databases using eternalbrowser authentication.

Features

• Test Connection: Verify connection to Snowflake and get current user/role information
• Execute Queries: Run SQL queries against your Snowflake database
• Schema Exploration: List databases, schemas, tables, and columns
• Table Metadata: Get detailed information about specific tables
• Secure Authentication: Uses Snowflake's eternalbrowser authentication for secure login

Tools Provided

1. test_connection: Test the connection to Snowflake and display connection info
2. execute_query: Execute arbitrary SQL queries with optional parameters
3. get_schemas: List available databases and schemas
4. get_tables: List tables in a specific database/schema
5. get_columns: Get column information for a specific table
6. describe_table: Get detailed metadata for a specific table

Installation

1. Clone this repository
2. Install dependencies:

   npm install
   

3. Copy the environment configuration:

   cp .env.example .env
   

4. Edit .env with your Snowflake connection details
5. Build the project:

   npm run build
   

Configuration

Set the following environment variables (or add them to your .env file):

• SNOWFLAKE_ACCOUNT: Your Snowflake account identifier (required)
• SNOWFLAKE_USERNAME: Your Snowflake username (required)
• SNOWFLAKE_DATABASE: Default database to connect to (optional)
• SNOWFLAKE_SCHEMA: Default schema to use (optional)
• SNOWFLAKE_WAREHOUSE: Default warehouse to use (optional)
• SNOWFLAKE_ROLE: Default role to assume (optional)

Authentication

This server uses Snowflake's EXTERNALBROWSER authentication method, which will open a web browser for you to authenticate with your Snowflake credentials. Make sure you have access to a web browser on the machine where this server is running.

Usage

Setting Up Environment Variables

Before running the server, you'll need to configure your Snowflake connection details. You can either:

1. Use environment variables (recommended for development):

   # Copy the example environment file
   cp .env.example .env
   
   # Edit .env with your details
   # SNOWFLAKE_ACCOUNT=your_account.region
   # SNOWFLAKE_USERNAME=your_username
   # etc.
   

2. Set environment variables directly:

   set SNOWFLAKE_ACCOUNT=your_account.region
   set SNOWFLAKE_USERNAME=your_username
   # etc.
   

Running the Server

For development:

npm run dev

For production:

npm run build
npm start

Using with Claude Desktop

To use this server with Claude Desktop, add the following configuration to your claude_desktop_config.json:

Windows: %APPDATA%\Claude\claude_desktop_config.json macOS: ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "snowflake": {
      "command": "node",
      "args": ["D:\\absolute\\path\\to\\dlh-snowflake-mcp-server\\build\\index.js"],
      "env": {
        "SNOWFLAKE_ACCOUNT": "your_account.region",
        "SNOWFLAKE_USERNAME": "your_username",
        "SNOWFLAKE_DATABASE": "your_database",
        "SNOWFLAKE_SCHEMA": "your_schema",
        "SNOWFLAKE_WAREHOUSE": "your_warehouse"
      }
    }
  }
}

Important: Use the absolute path to your build/index.js file.

Example Queries

Once connected, you can use the server to:

• Test your connection: "Test my Snowflake connection"
• Run queries: "Execute this SQL query: SELECT * FROM my_table LIMIT 10"
• Explore schema: "Show me all the databases and schemas"
• Get table info: "What tables are in the PUBLIC schema?"
• Describe tables: "Describe the structure of the CUSTOMERS table"

Development

Building

npm run build

Cleaning

npm run clean

Debugging in VS Code

You can debug this MCP server using VS Code:

1. Build the project: npm run build
2. The server is configured in .vscode/mcp.json
3. Use the VS Code MCP extension to connect and test

Security Notes

• This server uses eternalbrowser authentication for secure access to Snowflake
• Never commit your .env file or expose your Snowflake credentials
• The server logs to stderr to avoid interfering with MCP communication
• All SQL queries are executed with your authenticated user's permissions

Troubleshooting

1. Authentication Issues: Make sure you can access a web browser and that your Snowflake account supports eternalbrowser authentication
2. Connection Timeouts: Check your network connection and firewall settings
3. Permission Errors: Ensure your Snowflake user has the necessary permissions for the operations you're trying to perform
4. Environment Variables: Double-check that all required environment variables are set correctly
5. Build Issues: Make sure TypeScript compiles successfully with npm run build

License

ISC